Processors need to meet performance and power specifications. For example, processors typically require a single voltage to meet operation performance specifications. To accomplish this objective and optimize processing yield, it is a common practice to require a single voltage range for all integrated circuits (ICs) of a particular design. However, by requiring a single voltage, the manufacturing yield is reduced due to process variations. For example, manufacturing yield may be reduced because manufacturing processes will yield faster, higher power parts, as well as slower, lower power parts. As such, for example, faster, higher power parts will exceed the current limits or thermal designs of the system unless an unreasonably large thermal and/or power range is designed into the system.
To compensate for these process variations, some designs include multiple voltages for an IC with the IC providing the voltage requirements on output pins. In this scenario, the manufacturer will assign different part numbers for each group. This complicates the system manufacturing process. Another design approach is to use external pull-ups on the voltage selection pins to insure a valid voltage until the correct value can be output. This design approach is also problematic. For example, it requires specific power supply sequencing to prevent invalid transient power values as the IC powers up, adding complexity and cost to the system design.
Accordingly, there exists a need in the art to overcome the deficiencies and limitations described hereinabove.